Apparatus for the continuous production of metallic beryllium



July 15, 1958 5. J. MORANA 2,343,544

APPARATUS FOR THE CONTINUOUS PRODUCTION OF METALLIC BERYLLIUM Filed Dec. 22, 1955 3 Sheets-Sheet 1 H H0 Hb IN V EN TOR.

Simon J. Morclnu ATTYJ y 1958 s. J. MORANA APPARATUS FOR THE CONTINUOUS PRODUCTI 0F METALLIC BERYLLIUM Filed Dec. 22. 1955 3 Sheets-Sheet 2 I INVENIQRJ Simon J. Morena July 15, 1958 5. J. MORANA APPARATUS FOR THE 2,843,544 CONTINUOUS PRODUCTION OF METALLIC BERYLLIUM 5 Sheets-Sheet 3 Filed D86. 22, 1955 INVENTOR. Simon J. Morena BY mw 7ymu United States Patent APPARATUS FOR THE CONTINUOUS PRODUC- TION OF METALLIC BERYLLIUM Simon J. Morana, Reading, Pa., assignor to The Beryllium Corporation, Reading, Pa., a corporation of Delaware Application December 22, 1955, Serial No. 554,796

7 Claims. (Cl. 204--227) This invention relates to a new method and apparatus for the continuous production of metallic beryllium.

Prior art production of metallic beryllium utilizes batch processes and apparatus for carrying out such processes. These batch processes, however, are timeconsuming and expensive as compared with applicants continuous process and apparatus for the production of metallic beryllium as will be apparent from what follows herein.

An object of the present invention is to provide ways and means for the continuous production of metallic beryllium.

Another object of the invention is for the continuous production of metallic beryllium by electrolytic decomposition of beryllium chloride dissolved in a low-melting, fused-salt bath and wherein the electrolysis is performed in such manner that the metallic beryllium is deposited and recovered in the form of dendrites.

Another object of the invention is to provide new apparatus for the continuous production of metallic beryllium by electrolytic decomposition of beryllium chloride dissolved in a low-melting, fused-salt bath and wherein the electrolysis is performed in such manner that the metallic beryllium is deposited and recovered in the form of dendrites.

Another object of the invention is to provide new and improved apparatus for the continuous production of metallic beryllium and wherein the components comprising the same are disposed and related with each other in a novel manner and the apparatus permitting the constituents from which the metallic beryllium is formed to be readily introduced thereinto and the formed metallic beryllium removed therefrom either manually, semi-automatically or automatically.

Another object of the invention is to provide a new and improved process for the production of high purity beryllium metal wherein the conventionally used preelectrolysis step to purify the electrolyte is eliminated.

Other and more specific objects will become apparent in the following description of this invention as illustrated in the accompanying drawings wherein:

Fig. 1 is a top plan view of the multi-cell electrolysis unit for the continuous production of beryllium according to the present invention;

Fig. 2 is an axial sectional view of the apparatus shown in Fig. 1;

Fig. 3 is a sectional view taken on line 33 of Fig. 1;

Fig. 4 is a top plan view partly in section of a modification of the present invention;

Fig. 5 is an axial sectional view of the apparatus shown in Fig. 4;

Fig. 6 is a detail view of one part of the apparatus shown in Figs. 4 and 5;

Figs. 7, 8 and 9 illustrate successive stages in the re moval of the beryllium dendrites from the walls of the cathodes.

' In Figs. 1 and 2, there is disclosed one embodiment of ice apparatus for the continuous production of the metallic beryllium. This apparatus comprises a substantially rectangularly shaped cell containing tank 10 and embodies bottom, end and side walls and a closure 11 therefor and which closure may be and preferably is made in sections such as shown at Ila-f and is therefore easily removable. Each of said sections Ila-f is provided with downwardly depending flanges 11g as best shown in Fig. 3 for maintaining the same in fixed, aligned relationship to the tank 10. i

The tank is provided, preferably at one end thereof with a sump 12 into which the formed metallic beryllium is deposited as later herein described. The upper portion of the tank is provided with a plurality of channel type spacing reinforcement members 13 which have depending therefrom a plurality of tubular, nickel, substantially similarly formed cathodes 14 having a flange portion 14a and which, as shown, are in spaced-apart aligned relationship with each other. These cathodes are fixedly secured to the reinforcement members 13 in any desired manner. In order to facilitate the removal of the beryllium deposits from the cathodes and prevent contamination thereof by the nickel cathode, each of the cathodes 14 is preferably provided with a concentrically arranged graphite or like sleeve 15. These sleeves are preferably preformed and frictionally fitted but, of course, the

graphite or the like may be otherwise applied interiorly.

to the tubular cathodes. The cathodes and the graphite or like sleeves are preferably coextensive in length. It has been found that without the graphite sleeves, the beryllium has a tendency to adhere to the base nickel on which it formed a tightly held sponge-like coating which was difficult to remove on a continuous basis. The graphite sleeve does not interfere with the electrolysis and provides a surface from which the beryllium flakes olf clean as later described. Additionally, it has been found that by using the conventional nickel cathode there is an unusually high nickel contamination in the collected beryllium dendrites. I have found that by covering the inside of the nickel cathode with a thin graphite liner or sleeve, the beryllium dendrites deposit onto the graphite liner or sleeve and there is no pickup of nickel due to fusion of the beryllium dendrites onto the nickel cathode that was previously experienced.

The closure 11 is provided with a plurality of apertures 16 adapted to receive therein vertically extending reciprocable rods 17. The inner ends of said rods have fixedly secured thereto a circular, vertically reciprocable, dendrite removal means in the form of a ring 18, the outside diameter of which is such as to space the same inwardly from the inner surface of the graphite sleeves. It will be noted that the corners of the rings are squared so as to prevent the same from digging into and removing the graphite if the ring tilts during the dendrite removal operation. It is understood, of course,

that the rings 18 are the same in each of the cells that are formed by the tubular nickel cathode-s and the concentric graphite sleeves and a description of one of these rings serves for all of them. The tank 10 is, of course, filled with the fused salt electrolyte, the fluid level being shown at F.

Centrally disposed with respect to each of the aforesaid cells is a carbon anode, 19 which extends through an opening 20 in the closure 11. An insulating bushing 21 overlies and is held in place over the opening by bolts 21a or the like in order to insulate the anode from its closure. A ring clamp 21b holds each of the anodes in position. The lower portion of the anode as seen'from Fig. l, is disposed substantially centrally within each of the cells. Each of the anodes also has terminalsZZ at its end portion exteriorly of the tank and is connected 3 in a conventional electrical circuit denoted generally at 23, the negative connection being made to a bolt 23a aflixed to the tank and the positive connections to the anodes of the cells.

The closure above each of the cells is provided With a suitable vent 24 for gases forming in the tank. In order to provide access to the sump 12, the closure 11 at one end thereof, above the sump, is preferably provided with a hinged closure 25.

As will be seen from Fig. 1, there is a slot 26 in the closure 11 thatextends longitudinally of the tank and up to a point adjacent the sump. This slot allows for the insertion of an L-shaped scraper 27 as best shown in Fig. 3, which comprises an upstanding arm 28 with a portion 29 thereof extending through and beyond the slot and a lower scraping arm 30 which is actually in engagement with theinner surface of the bottom wall 31. The slot 26 extending substantially the length of the tank, therefore, enables'one to grip the portion 29 and move it relative to the tank with the bottom arm 30 thereof resting 'thereon and thereby move the accumulated dendrites to the sump 12 and into the perforated receptacle S. When the scraper is not in use, it can be totally removed from the tank and in order to close the tank, there'is provided a swinging hinged type closure 32 for closing the slot 26.

In order to remove the accumulated metallic beryllium from the sump 12, any suitable means, of course, may be used but it is found that an effective manual means of removal is a perforated receptacle S which has attached thereto a suitable handle or the like H, and the handle being of such length as to enable the receptacle to be reinserted into the bottom of the sump. In normal operation, the perforated receptacle is maintained in fixed position in the sump, only being removed for periodic removal of metal. The receptacle is perforated so that when the beryllium is removed, the electrolyte drains through the perforations back into the tank. Instead of this receptacle, a perforated ladle-like scoop may be used to effect the removal of the accumulated beryllium. Suitable heating means, either electric or otherwise, is provided such as diagrammatically illustrated at 10'.

The aforesaid apparatus, as is obvious, is manually operable and controllable.

The aforesaid apparatus is one embodiment for the mechanical carrying out of the process hereinafter referred to.

In Figs. 4 and 5, there is more or less diagrammatically illustrated an apparatus which is automatically operable and the automatically operable features are the provision of a pair of hydraulic or pneumatic cylinders C preferably attached by means of brackets or otherwise 33 to the end walls W of the tank. These cylinders are preferably similarly formed and of the same dimensions and each includes a piston P thereon, and suitable openings adjacent end portions of each of the cylinders whereby the hydraulic or pneumatic fluid from a suitable source including a pump may be introduced for reciprocating the pistons in the cylinder.

Connected with each of the pistons there is a yoke Y which extends from one of the pistons to the other in their respective cylinders. This yoke Y has attached thereto the rods 17 which extend through the openings 16 in the closure and carry at their lower ends the dendrite removal rings 18.

The automatic means for removing the accumulated metallic beryllium from the sump comprises a perforated basket or the like 36 to the upper edges of which there are attached converging straps or the like 37, and to which straps there is removably attached a flexible cable 38, which cable is trained about a winch 39. Aftixed to the cable 38 is a stop member 38a.

, Preferably, directly above the end wall W of the tank, there is disposed a bracket 40, the upper end 41 of WhlCli is at a substantially right-angular relation and extends into the path of travel of the basket 36 as it is removed from the sump and the tank. The end 41 of bracket 40 is provided with an aperture 41a through which cable 33 passes. As the basket is moved upwardly by the winch, it will be seen that the stop member 38a on cable 38 will engage the under surface of end portion 41 of the bracket thereby stopping the travel of the basket 36. The basket 36 can then be easily removed for discharge of the accumulated metallic beryllium and a new basket attached and lowered into position. This is of no inconvenience since the basket is normally dumped only once a day. Further, it will be noted that the basket, when it is being raised, is in the path of the end portion of the tank when the closure is in open position, thereby permitting a drainage of the solution from the basket back into the tank.

The L-shaped scraper 27, in the embodiment shown in Fig. 3, has an upper end thereof 27' extending outwardly at a right angle thereto. The end of this extension is attached at 42 to an endless belt 43 or other such structure which may be electric motor or otherwise driven, not shown, so as to reciprocate the scraping arm 30 on the interior surface of the bottom of the tank.

Heretofore, it has not been possible to produce metallic beryllium in the form of dendritic flake in a completely continuous manner without interrupting the operation of the cell since the dendrites as they form grow radially inward toward the anode and ultimately short out the system thereby terminating the deposition. The operation of the cell must then be halted in order to clean out deposited metal.

It is, therefore, important to maintain the distance between anode and cathode a relative constant. I have found that by periodically knocking down or removing the longer dendrites, that the distance between the anode and cathode is maintained at a relative constant and uniform electrical characteristics are maintained within the cell and any tendency to short out is eliminated. The deposition process can therefore proceed in a completely continuous manner without any interruption whatsoever in the operation of the cell and without resort to batch type operation. The operator of the cell can tell when there has been an accumulation of dendrites requiring removal merely by watching the ammeter. If there has been a dendrite accumulation requiring removal, the current will fluctuate.

Referring to Figs. 5a, 5b and So, there is more or less diagrammatically illustrated successive steps in the knocking down or removal of the longer dendrites from the cathode, Fig. 5a showing condition before dendrite removal, 5b during dendriteremoval, and Fig. 50 after removal of dendrites. It will be appreciated that while only one cathode has been shown, that a similar operation takes place either simultaneously or selectively at each of the other cathodes. As can be seen and as previously described, the dendrites tend to grow radially inward toward the anode in tree-like formations. Periodically, at least hte longer dendrites are removed by reciprocation of ring 18 thereby knocking these dendrites loose and allowing them to gravitate to the bottom of the cell where they are periodically scraped to one end and removed from the cell as heretofore described. By the periodic removal of the dendrities from. the wallsof the cathodes, the distance between the anode and cathode is maintained a relative constant thereby preventing shorting of the cell and the operation of the cell proceeds completely continuous without any interruption in'the operation of the cell.

While Figs. 1-6 depict a three-cell unit, it will be understood that any number of cells from one to an indefinite number can be used in the same manner. My experiments have shown that there is no decrease'in current efliciency by the operation of a multi-cell unit as compared with the 7 operation of a single cell unit.

In bothtbe manual and automatically operated apparatus there is incorporated in the electric circuit ammeters A for each of the anodes and an additional ammeter A. The ammeters A individually indicate the amperage of each of the cells respectively while the ammeter A gives a total amperage reading. The circuit is also provided with a voltage meter V which gives the voltage reading for the electrolysis unit. While the circuit here has been shown wired in series it will be understood that modifications can be made to wire the same in parallel.

In both forms of apparatus depicted, the electrolyte used is a low melting fused mixture of beryllium chloride and sodium chloride. More specifically, I have found that the BeCl concentration in the fused salt is somewhat critical. While the percentage of BeCl can vary from 40-70%, I have determined that when the BeCl concentration is above 60%, the carbon electrode life is 2-3 days, whereas when the BeCl concentration is below 55%, and preferable 53-55%, the life expectancy of the carbon electrode is much longer.

As an illustration of the processes of the present invention, the following examples are given.

Example 1 In the 3 unit cell as depicted in Figs. 1 and 2, each cell is 9.5 inches in diameter with a graphite inner liner 9 inches in diameter, and the overall bath size is 12 inches wide, 37 inches long and 15 inches deep. The apparatus is constructed completely of nickel with the exception of the graphite inner cell liners and the carbon anodes immersed in the center of each cell. The electrolyte is composed of a fused mixture of 55 BeCl and 45% NaCl which is maintained at a temperature between 300 and 400 degrees C. and preferably 350 C. throughout the electrolysis. The cell is run continuously on a 24 hour basis, and the BeCl consumed in the electrolysis is periodically replenished with distilled BeCl crystals. The beryllium dendrites formed on the walls of the cathode are periodically removed therefrom during the operation of the cell to maintain the distance between the anode and cathode a relative constant and prevent shoring out of the system. The beryllium dendrites are collected once a day, washed with ice-chilled water to remove adhering electrolyte, dried, and then washed with concentrated nitric acid.

During a 31 day operating period, a total of 85 pounds of beryllium flake was produced, for an average daily production of 2.75 pounds. During this time 1,050 pounds of beryllium chloride and 124 pounds of sodium chloride were consumed. Each single cell was operated at 150 amperes, totaling 450 amperes for the 3-cell unit. According to Faradays laws of electrolysis 450 amperes should theoretically produce 4.0 pounds of beryllium metal per day, giving a current efliciency of about 70% for the above time period.

Based on the amount of beryllium contained in the beryllium chloride consumed, there should have been produced 3.82 pounds of beryllium metal per day. This gives us an overall beryllium recovery of 72% from chloride to metal. However, since a total of 124 pounds of salt was consumed to maintain the bath at the correct proportion, it might be assumed that this salt was contained in the electrolyte adhering to the metal flakes when they were drained in the process of daily removing the metal from the bath. If so, undoubtedly an equal weight of beryllium chloride was lost in that same operation (the electrolyte being practically at 5050 fused mixture). Deducting this amount of chloride from the total consumed in this 31 day operating period leaves a conversion efficiency of 82% from chloride to metal. The remaining 18% of beryllium chloride was consumed by evaporation during electrolysis, and by the formation of extreme metallic fines which were discarded in the washing operation. The beryllium content contained in the water soluble electrolyte and in the beryllium metal fines can Fe Al Nl Mg C0, Zn, Cr, Ag, and Ca are reported not detected.

Example 2 The cell was designed to operate in a continuous manner, and contained a nickel cathode 18 inches diameter by 22 inches long. A 4-inch diameter carbon electrode was radially centered, and was immersed in the electrolyte about 12 inches. The fused electrolyte consisted of a mixture of 55% BeCl -4S% NaCl which was maintained at 350-375 C. throughout the run. The cell was operated at 500 amperes and 5.5 to 7 volts.

For the majority of the runs, the beryllium chloride added periodically to replenish the spent chloride in the electrolyte was purified by pre-electrolyzing 15 pound increments of BeCl for 3 hours at 56 volts and amperes in a smaller cell 9 inches in diameter.

The beryllium flakes were scraped off periodically from the cathode inner wall, and were allowed to fall to the bottom. Once a day the electrolytically produced beryllium was. removed by scraping the flakes to one side of the bottom into a perforated nickel container. The container was raised above the liquid level, and excess electrolyte was allowed to drain back. The drained metal was leached free of residual salts by dunking in ice water, followed by a more thorough washing with warm tap water. The electrolysis was kept on continuously, even while replenishing the bath or removing the metal.

The single electrolysis unit used in this investigation produced an average of 3.25 pounds of beryllium flake per day. A projected 5-cell unit of the same unit dimensions should produce about 16 pounds of beryllium metal per day, or about 500 pounds per month on a continuous basis. Thus, it should be possible to obtain 1000 pounds of high purity beryllium metal per month by operating two of these 5-cell units simultaneously.

During an approximate 2-month period 149.5 pounds of high purity beryllium flake was prepared with an accompanying total consumption of 1932 pounds of beryllium chloride, with an average production rate of 3.25 pounds per day. The overall beryllium metal recovery based on the calculated amount of beryllium contained in the BeCl charged was 68%. This includes losses in the pre-electrolysis stages, volatilization losses by entrainment with exhaust chlorine gas, losses by hydrolysis when water-washing the flake, etc.

by omitting the pre-electrolysis step of the above example, with a consumption of 295 pounds of BeCl This resulted in an improved overall efficiency of 84% based on the weight of chloride charged. In both cases it was found that a final wash in concentrated nitric acid improved the flake in appearance, and minimized its chemi cal impurities. Composite analyses of the metals obtained both with and without acid washing are as follows:

These results are all in percent; Mn, Co, Zn, Ag, and Ca are reported not detected.

These results clearly show that all metal should be acid washed. In so doing, metal prepared with no pre-electrolysis has approximately the same purity level (except for slightly higher Ni content) as that prepared with preelectrolysis.

Prior to my invention, it had been necessary in order to obtain a high purity beryllium metal to pre-electrolize the electrolyte in order to purify the same prior to the electrolytic deposition of the metal.

As can be seen from the above examples, I have found that I can prepare a high purity grade of beryllium metal in a completely continuous manner without the necessity of a preliminary pre-electrolysis purification step. In my process the replenishing beryllium chloride is added periodically as needed with no preliminary purification, and by washing the resulting beryllium metal with an ice water wash followed by a wash with concentrated nitric acid the purity level is equal to if not higher than that produced with the conventional pre-electrolysis.

The complete process is carried out as follows:

The electrolysis unit is initially filled with a fused salt mixture consisting of 40-70% beryllium chloride, balance sodium chloride (preferably 55% beryllium chloride), the cell is closed and the salt mixture heated to and maintained at a temperature of 300-450 C. (preferably 350380 C.). The electrolysis is then begun to deposit beryllium dendrites onto the cathode surface. These dendrites will grow radially inward toward the anode, therefore periodically the longer dendrites are removed by knocking them off the walls of the cathode to the bottom of the cell without interrupting the operation of the cell, the accumulated dendrites being periodically scraped from the bottom surface to a sump and subsequently removed from the cell. The dendrites after being removed from the cell are subjected to an ice water wash to remove any electrolyte that might adhere, then dried, and purified by washing with concentrated nitric acid.

I have found that the ammeter and volt meter serve as a visual indication as to when it is necessary to remove or knock down the dendrites. When the ammeter reading begins to waver and the voltage drops the dendrites should be knocked down thereby restoring the current efliciency of the cell.

The beryllium chloride consumed in the processing is replenished by adding additional beryllium chloride directly to the cell as needed without a pre-electrolysis.

Referring to Figs. 7, 8 and 9, there is diagrammatically shown a sequence of operations in the removal of the dendrites. In Fig. 7 the dendrites (which are shown here in enlarged condition for simplicity of illustration) have grown radially inward toward the anode and are reaching a point where continued growth will decrease the current efficiency and ultimately short out the cell. In Fig. 8 the dendrites are being removed and are gravitating to the bottom of the tank. Some of these dendrites break completely from the cathode surface While others leave a small'portion remaining. Fig. 9 shows the cell with dendrites removed and the dendrites removal ring back in position.

In conclusion, it can readily be seen that I have provided a new and improved process for continuously producing metallic beryllium in the form of dendritic flakes 8 together with new andimproved apparatus for carrying out the process.

Having now explained my invention, I claim:

1; Apparatus for the continuous production of beryllium comprising a tank having top, bottom and side walls, a vertically disposed, rod-like anode rigidly supported from the top wall for projection downwardly into said tank, a vertically disposed cylindrical cathode shell rigidly suspended for projection downwardly into said tank in spaced relation to the tank side walls and in spaced concentric surrounding relationship with the said anode, the shell having its lower end open and spaced from the bottom wall of the tank, an electric power source connected to said cathode and anode for electrolyzing a beryllium containing electrolyte in which the cathode and anode are suspended for passage of electric current therebetween through beryllium containing electrolyte to effect formation of beryllium dendrites on the inner wall of said cathode, a ring surrounding said anode and having its periphery disposed closely adjacent to the inner wall of the associated cathode, and means operatively connected to said ring for effecting vertical movement of the ring to remove beryllium dendrides from the wall of the cathode for discharge through the open bottom of the electrode shell during operation of the cell.

2. Apparatus as defined in and by claim 1, wherein said bottom wall has a sump at an elevation below and to one side of the cathode shell, a scraper movable across said bottom wall of the tank for gathering beryllium deposited on the bottom wall of said tank and moving it therealong toward and for collection in the sump within the tank and means for effecting movement of the scraper back and forth over the bottom wall.

3. Apparatus as defined in and by claim 1, wherein said cathode shell is metal lined with a graphite cylinder.

4. Apparatus as defined in and by claim 1, wherein each of said cathode shells is of nickel lined with graphite.

5. Apparatus as defined in and by claim 1, wherein said bottom wall has a sump therein to one side of the bottom wall area above which the open lower end of the cathode shell lies, a scraper movable on the bottom wall across said area toward and away from said sump, means connected with the scraper and operable from outside the tank to so move the scraper, a receiving receptacle in said sump having its top approximately at the level of the top surface of the bottom wall, and means connected with said receiver for raising the receiver from the tank.

6. Apparatus for the continuous production of beryllium comprising an electrolysis cell including a tank, '1 cylindrical cathode shell suspended within said tank and having its lower end spaced above the bottom wall thereof, said lower end of the shell being open to the full inside diameter thereof, a vertically disposed rod-like anode positioned concentrically within said cathode shell, an electric power source connected to the cathode and anode for elcctrolyzing electrolyte within said tank and effecting formation of beryllium dendrites on the inner wall of the cathode, a ring surrounding said anode and having its periphery disposed closely adjacent to the inner wall of said cathode, and power means operatively connected to said ring for effecting periodic movement of the ring axially of said anode to detach beryllium dendrites from the inner wall of said cathode for discharge through the open lower end of the shell onto said bottom wall without interrupting operation of said cell.

7. Apparatus for the continuous production of beryllium comprising an electrolysis cell including a tank, a series of vertically disposed cylindrical cathode shells disposed within the confines of said tank and each having its lower end spaced above the bottom wall of the tank, each of said shells being open at its bottom end, a vertically disposed rod-like anode disposed concentrically within each cathode shell, an electric power source connected to the cathode and anode for electrolyzing a beryllium containing eleotrolyte within the tank to effect depositing of beryllium onto the inner walls of said cathode shells, a ring surrounding each of said anodes and having its periphery disposed in close adjacency to the inner wall of a corresponding cathode shell, means for moving said rings vertically axially of said anodes and cathodes to remove deposited beryllium from the inner wall of the cathodes without interrupting operation of the cell and whereby such removed berryllium falls to the bottom of said tank, and a scraper assembly movable along the bottom wall of said tank to harvest beryllium from beneath said cathode shells and moving the same to a predetermined collection point within said tank.

10 References Cited in the file of this patent UNITED STATES PATENTS 2,748,073 Mellgren May 29, 1956 2,752,303 Cooper June 26, 1956 FOREIGN PATENTS 434,338 Great Britain Aug. 29, 1935 860,281 Germany Dec. 18, 1952 OTHER REFERENCES Metal Industry (London), June 14, 1946, pages 469 and 470. 

1. APPARATUS FOR THE CONTINUOUS PRODUCTION OF BERYLLIUM COMPRISING A TANK HAVING TOP, BOTTOM AND SIDE WALLS, A VERTICALLY DISPOSED, ROD-LIKE ANODE RIGIDLY SUPPORTED FROM THE TOP WALL FOR PROJECTION DOWNWARDLY INTO SAID TANK, A VERTICALLY DISPOSED CYLINDRICAL CATHODE SHELL RIGIDLY SUSPENDED FOR PROJECTION DOWNWARDLY INTO SAID TANK IN SPACED RELATION TO THE TANK SIDE WALLS AND IN SPACED CONCENTRIC SURROUNDING RELATIONSHIP WITH THE SAID ANODE, THE SHELL HAVING ITS LOWER END OPEN AND SPACED FROM THE BOTTOM WALL OF THE TANK, AND ELECTRIC POWER SOURCE CONNECTED TO SAID CATHODE AND ANODE FOR ELECTROLYZING A BERYLLIUM CONTAINIGN ELECTROLYTE IN WHICH THE CATHODE AND ANODE ARE SUSPENDED FOR PASSAGE OF ELECTRIC CURRENT THEREBETWEEN THROUGH BERYLLIUM CONTAINING ELECTROLYTE TO EFFECT FORMATION OF BERYLLIUM DENDRITES ON THE INNER WALL OF SAID CATHODE, A RING SURROUNDING SAID ANODE AND HAVING ITS PERIPHERY DISPOSED CLOSELY ADJACENT TO THE INNER WALL OF THE ASSOCIATED CATHODE, AND MEANS OPERATIVELY CONNECTED TO SAID RING FOR EFFECTING VERTICAL MOVEMENT OF THE RING TO REMOVE BERYLLIUM DENDRIDES FROM THE WALL OF THE CATHODE FOR DISCHARGE THROUGH THE OPEN BOTTOM OF THE ELECTRODE SHELL DURING OPERATION OF THE CELL. 